On 2014-04-24 00:07, H Hartley Sweeten wrote:
The chanlist is checked in Step 5 of the (*do_cmdtest) there is no
reason to check it again in the (*do_cmd). The only reasonm its done
is to get the actual 'seglen', the non-repeating length of the chanlist.
Save the 'seglen' found by pci171x_ai_check_chanlist() in the private
data and use that in the (*do_cmd).
Since do_cmdtest can be done while a command is running, one needs to be
careful to make sure that any private data modified by do_cmdtest is not
used by the running command, and only used by do_cmd when setting up the
next command.
It's fine in this case though as devpriv->act_chanlist_len is only used
while setting up the next command, although perhaps it ought to be
renamed to devpriv->saved_chanlist_len, possibly by a subsequent patch.
(Also, devpriv->act_chanlist_pos isn't used so can be removed.)
Refactor the error handling in pci171x_ai_check_chanlist() to work like
the cfc_check_*() helpers.
Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>
Cc: Ian Abbott <abbotti@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/staging/comedi/drivers/adv_pci1710.c | 29 +++++++++++++++-------------
1 file changed, 16 insertions(+), 13 deletions(-)
diff --git a/drivers/staging/comedi/drivers/adv_pci1710.c b/drivers/staging/comedi/drivers/adv_pci1710.c
index 59c8bc4..6698d3c 100644
--- a/drivers/staging/comedi/drivers/adv_pci1710.c
+++ b/drivers/staging/comedi/drivers/adv_pci1710.c
@@ -330,6 +330,7 @@ static int pci171x_ai_check_chanlist(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_cmd *cmd)
{
+ struct pci1710_private *devpriv = dev->private;
unsigned int chan0 = CR_CHAN(cmd->chanlist[0]);
unsigned int last_aref = CR_AREF(cmd->chanlist[0]);
unsigned int next_chan = (chan0 + 1) & s->n_chan;
@@ -337,8 +338,10 @@ static int pci171x_ai_check_chanlist(struct comedi_device *dev,
unsigned int seglen;
int i;
- if (cmd->chanlist_len == 1)
- return 1; /* seglen=1 */
+ if (cmd->chanlist_len == 1) {
+ devpriv->act_chanlist_len = cmd->chanlist_len;
+ return 0;
+ }
/* first channel is always ok */
chansegment[0] = cmd->chanlist[0];
@@ -353,7 +356,7 @@ static int pci171x_ai_check_chanlist(struct comedi_device *dev,
if (aref == AREF_DIFF && (chan & 1)) {
dev_err(dev->class_dev,
"Odd channel cannot be differential input!\n");
- return 0;
+ return -EINVAL;
}
if (last_aref == AREF_DIFF)
@@ -362,7 +365,7 @@ static int pci171x_ai_check_chanlist(struct comedi_device *dev,
dev_err(dev->class_dev,
"channel list must be continuous! chanlist[%i]=%d but must be %d or %d!\n",
i, chan, next_chan, chan0);
- return 0;
+ return -EINVAL;
}
/* next correct channel in list */
@@ -381,10 +384,12 @@ static int pci171x_ai_check_chanlist(struct comedi_device *dev,
CR_CHAN(cmd->chanlist[i % seglen]),
CR_RANGE(cmd->chanlist[i % seglen]),
CR_AREF(chansegment[i % seglen]));
- return 0;
+ return -EINVAL;
}
}
- return seglen;
+ devpriv->act_chanlist_len = seglen;
+
+ return 0;
}
static void setup_channel_list(struct comedi_device *dev,
@@ -396,7 +401,6 @@ static void setup_channel_list(struct comedi_device *dev,
struct pci1710_private *devpriv = dev->private;
unsigned int i, range, chanprog;
- devpriv->act_chanlist_len = seglen;
devpriv->act_chanlist_pos = 0;
for (i = 0; i < seglen; i++) { /* store range list to card */
@@ -953,7 +957,6 @@ static int pci171x_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
struct pci1710_private *devpriv = dev->private;
struct comedi_cmd *cmd = &s->async->cmd;
unsigned int divisor1 = 0, divisor2 = 0;
- unsigned int seglen;
int mode;
if (cmd->convert_src == TRIG_TIMER) {
@@ -967,10 +970,8 @@ static int pci171x_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
start_pacer(dev, -1, 0, 0); /* stop pacer */
- seglen = pci171x_ai_check_chanlist(dev, s, cmd);
- if (seglen < 1)
- return -EINVAL;
- setup_channel_list(dev, s, cmd->chanlist, cmd->chanlist_len, seglen);
+ setup_channel_list(dev, s, cmd->chanlist, cmd->chanlist_len,
+ devpriv->act_chanlist_len);
outb(0, dev->iobase + PCI171x_CLRFIFO);
outb(0, dev->iobase + PCI171x_CLRINT);
@@ -1104,7 +1105,9 @@ static int pci171x_ai_cmdtest(struct comedi_device *dev,
/* Step 5: check channel list */
- if (!pci171x_ai_check_chanlist(dev, s, cmd))
+ err |= pci171x_ai_check_chanlist(dev, s, cmd);
+
+ if (err)
return 5;
return 0;
--
-=( Ian Abbott @ MEV Ltd. E-mail: <abbotti@xxxxxxxxx> )=-
-=( Tel: +44 (0)161 477 1898 FAX: +44 (0)161 718 3587 )=-
_______________________________________________
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxx
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
